Solvent extraction of cobalt and nickel from chloride solution by mixtures of acidic organophosphorous extractants and amines

Abstract

In order to extract Co and Ni from the chloride solution with low initial pH (1–3), solvent extraction experiments were performed by employing the mixture of organophosphorous extractants (D2EHPA, PC 88A and Cyanex 272) and amine extractants (Alamine 336, Alamine 308, and Alamine 300). Among the studied mixtures, a mixture of Alamine 308 and Cyanex 272 showed the best efficiency for the selective extraction of Co (63%) over Ni from chloride solutions with an equilibrium pH of 4.9. Although Co was not extracted by each single extractant, the synergism was observed for Co extraction using this mixture. Moreover, it was possible to selectively extract Co over Ni using the mixture of Alamine 308 and Cyanex 272.

Keywords:

• Cobalt
• nickel
• mixture extractants
• synergism

Acknowledgments

We gratefully thank the Gwangju branch of the Korea Basic Science (KBSI) for ICP data.